Nick, I suggest a road trip on your next day off. Grab you some cash and get out of town. Take the backroads toward the bigger cities and expand out from there. You have to out think your competition. With that huge Indy town so close, you can bet it is full of searchers. So try something else other than Indy. A simple google search for banks in your area turned up a $hitload of banks that are all potential hot beds. On a typical road trip, I will hit at least 40-50 banks. If you hit an area that the tellers all say "someone gets them from us all the time" move to another area. Try some credit unions, they are not great for halves but they get a lot of other change.
One thing you might try if you are a wee bit ambitious. My part of the world has umpteen video game joints. They all get tonnage of quarters. These owners pick out the silver but you can buy them right. Other spots for a lot of change are laundromats,especially near colleges.
Good luck,don't give up, we have all developed a style, you will too. Jim